The primary difference with shotguns is there exists factory ammo that far exceeds the range you will find for commercial pistol ammo. The power factor (load weight x velocity) of 45 ACP pistol ammo ranges from 157 PF at the lightest to 218 PF for +P loads. The lightest commercial load is still at 72% of the heaviest and will likely have enough energy to cycle the action if set up for the hottest load without damaging anything.
Autoloading shotguns are being asked by the ammo makers to cycle 375 PF cowboy loads to 1138 PF magnum turkey loads. The lightest load is only at 33% of the heaviest. If set up to handle the heaviest load, the lightest will not have anywhere near enough energy to cycle the lightest. Unfortunately, if you are set up to handle the lightest, you will damage the gun trying to run the heaviest.
The 930/935 gas system has a secondary that bleeds excess off and allows from the factory, the ability to run about 500 PF to 750 PF all day long. This lightest load is about 63% of the hottest, which is a much better ability to run a wide range of loads than a 45 ACP pistol. It just doesn't cover all that is available for ammo. The secondary gas system in the 930/935 allows slightly hotter loads to be run in moderation, while lighter loads will malfunction unless all sources of friction and resistance are greatly reduced.
This is why we have a line of Competition parts that are different than the Multi-Use parts. This is also why the ASR is important for adjusting the recoil assembly to the correct range. The Quick-Adjust ASR allows use of the extremes in most 930s/935s, but requires a setting change when going between them because it simply isn't practical for the same configuration to run every 12 Gg shell on the market. Get your 930 slicked up and eliminate as many sources of friction as possible and the range will open considerably.
William
http://www.OR3GUN.com